George,
Our very own AndyO has done a write up here:
http://24heuer.blogspot.co.uk/2011/06/dont-try-this-home-rolex-faded-bezel.html

I followed his advice & had a crack myself on an old diver insert.. (never tried on a Autavia insert though - although James has & it was successful.)
This is my advice:

Household bleach in a bowl, enough to cover the insert & bezel. Drop in insert right way up for 2 mins, remove & rinse. Wipe gently with kitchen towel.
Repeat, but shortening the dunk time as you get closer to the shade you want.
Word of warning - the insert will continue to fade slightly for a minute or so after rinsing, so take your time.
The inserts have a gloss coating.. when this is removed, it will have a matt look, which is very nice. This top coating may take several 2-3 min dunks to remove, you'll be able to see it & if you've missed any.
After this top layer is removed, the fading accelerates rapidly, so reduce dunk time to 30 secs.

If the insert has scratches or wear areas already, these will fade/bleach much quicker than 'clean' areas of the bezel, this can be bad - I have ruined an insert because of this.

Good luck!
Stewart

: So i have a used 11630 bezel which i want to use for the experiment
: was wondering if any of you have experience?